Electrically uncharged atoms with an unpaired electron. They steal or give up an electron to another causing an injurious bond which forms with carbohydrates, proteins, and lipids. They ultimately destroy plasma membrane.

Diseases implicated by free radicals.

Atherosclerosis
Cancer
Diabetes
Alzheimer's disease

Mechanisms of Injury / Effects of Free Radicals

Lipid Peroxitation, Polypeptide Fragmentation, Alterations in the DNA

Lipid Peroxitation

descruction of unsaturated fatty acids which produces peroxides which are detrimental to the plasma membrane and organelles

Reaction with thiamine in DNA causing breaks in the DNA / malignant transformation

Name 6 reversible cellular injuries

Hydropic
Atrophy
Hypertrophy
Hyperplasia
Metaplasia
Dysplasia

Atrophy

Cellular swelling caused by the movement of extracellular water into the cells. Happens with hypoxia. Movement of water and ions into the cells is associated with metabolic failure an loss of ATP production

What happens, in terms of water and ions, if the Na+ / K+ pump fails.

Na+ in the cell increases the cells Osmotic Pressure and draws more water into the cell

Osmosis

the movement of water towards less water, or where there are more solutes

*Growth of uterus during pregnancy due to estrogen stimultion
*Breast enlargement due to prolactin stimulation
*Muscle enlargement due to anabolic steriods
*Increased work deman on striated skeletal muscles

Wet gangrene: result of liquefactive necrosis (neurophils) common in internal ordans. Site is cold and swollen, foul odor from pus, can become systemic, leading to death

Gas gangrene: Caused by infection of injured tissue by anaerobic bacteria. Produces hydrolytic enzymes and toxins that destroy connective tissue and PM of man cells including RBC. Gas bubbles form in muscle tissues. Is very dangerous when RBC become involved/lyse